Timing device



E, SHIPTON 2,336,897

TIMING DEVICE Filed April 21, 1939 4 Sheets-Sheet l k (Log/ 5277457? N v 2 f REA/4Y5 [g I n venfor A ttorney;

Dec. 14, 1943. E. SHIPTON 2,336,897

TIMING DEVICE 47' TOR/V1915 SHIPTON TIMING DEVICE Dec. 14, 1943.

Filed April 21, 1939 4 Sheets-Sheet 3 1 7% m wfi H w b. E% w ATTORNEYS Dec. 14, 1943.

/0 55a sw/rcH E. SHIPTON 2,336,897

TIMING DEVICE Fig. 4.

I556 SWITCH sporting events, where Patent ed no. '14, 1943 TIMING DEVICE I 'Edward Shi-pton, London, England Application April 21, 1939, Serial No.

In Great Britain April 25, 1938 10 Claims. (01. 161.-)

The presentv invention relates to an electrical circuit arrangement suitable for indicating time.

In the specification of my prior British Patent No. 466,861, I have described a numerical time indicator comprising a field of lamps or illumi-.

nated strips which are illuminated in various combinations to indicate numbers, and a rotary switch having a plurality of contact banks and associated wipers which are stepped round by a stepping magnet, the :contacts being connected to indicate various numbers in accordance with the position '01 the wipers, the electrical impulses for operating the magnet being fed thereto at regular intervals of time.

The present invention relates to an improvement or modification of such an arrangement and also to a circuit arrangement for producing the timed impulses.

. According to the present invention a numerical time indicator comprising a field of lamps or illuminated strips which are illuminated in various combinations to indicate numbers, is constructed to indicate very short periods of time, such as 100ths of' a second, thus providing a stop watch which may be used for automatically timing races, such as dog races and other a timed accuracy of this degree is important. Since it is impossible to operate selecting switches at such high speeds, a feature of the invention consists in causing the high speed impulses to operate relays or other quick acting devices which mark positions on the contacts of selecting switches, such as rotary switches, so that, when th impulses are stopped, a definite contact is marked corresponding to the last relay or the like to operate. A switch is then operated, preferably simultaneously with the operation of the stopping switch, to start the selector switch hunting to find the marked contact, upon which contact it stops. Correspondclicate the various numbers. Preferably this indicator comprises gas discharge tubes, such as neon tubes. Alternatively, mechanical indicators may be used. A still further feature of the invention consists in a control unit for the indicator of such a stop watch" whereby a plurality of such indicating devices at different places may be simultaneously operated from the single control unit. A

Another feature of the invention consists in the use of an automatic telephone switch for operating the lamps or illuminated strips in such a stop watch. s v A further feature of the invention consists in using the positive and negative halves of 50- cycle mains supply current, preferably time controlled mains, for furnishing the 100th second impulses for operating a time indicator for indicating 100ths of a secpnd. Thi is preferably eiiected by employing two gas filled relays arranged in opposition, one of which is actuatedby the positive half cycle and the other by the negative hall. cycle.

ing to this position the lamps of the indicator are illuminated to tion.

From another aspect, therefore, the invention give a corresponding indicaconsists in employing the impulses which are too fast to operate th rotary switches to mark.

positions thereon, and subsequently to causes rotary switch to hunt to find the marked contact when the high speed impulses are stopped.

A further feature of the invention consists in a stop watch .wherein the time registered is automaticallyindicated on an indicator comprising' a field of lamps or illuminating strips,'which .A still further feature of th invention consists in a control circuit arrangement employing two gas discharge relays in opposition and connected to ,a source of alternating current, the

lcircuit arrangement associated being such that the gas discharge relays are automatically energised and de-energised alternately.

The numerical indications may be switched in to indicatethe time period measured after the control unit has stopped, or, alternatively, some of the denominations may operate continuously during the operation of the control unit, the remaining denominations being switched in after the control unit has been stopped. Of course, all the denominations could be indicated during the operation of the control unit, but since the lamps indicating the 10ths second and 100ths second would merely indicate a blur, it is preferable that these should only be illuminated after the control unit has been stopped.

In order that the invention may be more clearly understood an embodiment thereof applied to an electrical stop watchiiorindicating 100ths of a second will now be described with reference to the are'illuminated in various combinations to ixiaccompanying drawings, in which:

Fig. 1 shows a circuit diagram of an embodiment according to the invention, Fig. 2 shows some details either omitted from, or only indicated diagrammatically in, Fig. 1,

Figs. 3 and 3A show the interconnection between some of the wipersoi the rotary switches and posing the potential on cientlynegative to prevent the associated relays and the like to illustrate the operation of the switches, and

Fig. 4 shows other wipers of some of the switches shown in Figs. 3 and 3A for actuating I time indicating units.

Referring first to Fig. l, the 100th second impulses are produced from the 50-cycle time controlled mains which are fed to a transformer T, I the extremities of th secondary winding of which are connected to the grids of two gas discharge relays V1 and V2. The midpoint of the secondary winding is connected to the cathodes of the two I tubes through a grid bias source GB and the output of each tube is fed through two series of relays. Also connected across the two anodes is a condenser 05 In the quiescent state. the grid control voltage of each gas-filled relay is sumciently negative to prevent the flow of anode current. Immediately the start switch is closed, 50-cycle. alternating current is applied to the grid transformer.

The control voltage on each grid will, therefore, be increased and decreased alternately depending upon the potential induced across the two halves of the secondary winding of the transformer '1' respectively.

The alternating potential difference across these two halves-of the transformer secondary is arranged such that when it is in opposition to the normal grid control voltage, the negative bias on th grid is reduced to a value below that at which the relay strikes, and anode current will, therefore, commence to flow. Once the anode current supplied from a source HT of high ten sion'current commences to flow it will continue at a steady value independent of any, variation I of the grid bias until the relay is re-set. when the valve strikes the anode current reaches its steady-value practically instantaneously.

When the valve is re=set the time taken for the anode current to collapse is dependent upon I the de=ionisation time of the valve and this may I last operated gas filled relay will not be extin- I guished but will continue its discharge, thereby assess? rupted until the negative potential on the gri is again reduced to the striking voltage.

When V1 is again struck V2 will be extinguished in a similar manner and the foregoing sequence of operation will continue so long as alternating current is applied to the transformer T.. By means of this arrangement the current is switched alternately through the chain oi relays in the anode circuits of the relays V1 and V2. As the resetting of each gas relay is dependent upon the striking of the other gas relay and alsosince the striking of this relay is dependent upon the reduction of the normal grid control voltage by an induced potential diflerence in the grid circuit, then on discontinuing the 50-cycle alternat ing current applied to the grid transformer, the

locking up any relays which may constitute the load in its anode circuit. Furthermore, since it is the striking of one relaywhich extlnguishes the other, there is no intermediate period in which neither relay is operating.

The main suply may, of course, be used viding current for the heaters, grid control voltage and. anode potential aswill now be more fully explained with reference to Fig. 2. The

-cycle alternating current is supplied to a transformer T1, having three secondary windings W1, W2, W3. The winding W1 is connected to the points a and b of the heaters of the relays V1 and V2, the mid-point of the winding WI being earthed. The winding W2 furnishes, by means of a rectifiergb, a filter circuit 11 and resistances H, the negative bias for the grids of the relays V1 and V2. The winding W3 furnishes, by means of rectifiers gin and gin and filter circuits fll and vary according to the characteristics of the cir-- to the potential difference acrms the load con- I Y nected in the anode circuit of the relay V1. when relay V2 is struck by variation of its control voltage the condenserIC will discharge through it, the potential of the condenser momentarily optheanode of the relay V1. The anode current through V1 will, therefore, be interrupted. Theca'pacity of the condenser C is arranged such that its discharge timeis slightly longer than the die-ionisation time of the valve. pletely de-ionised. and the gridregain control before the anode voltage is restored to normal. Simultaneously the alternating voltage across the secondary of T is building up such asto make the grid of V1 increasingly negative with respect to the cathode, and on the normal grid control voltage. However, the normal gridcontrol voltage is, in itself. suiilanode current through V1 re-starting. Obviously, therefore, the flow of anode current through V1 will'be interthis voltage is superimposed tion between the anode voltage and the grid con- I trol voltage, that is, for any given anode voltage fi the high tension anode current to the relays V1 and V2, the terminals i, 2 and 3 of the circuit shown in Fig. 2 being identical with the points I, 2 and 8 shown in Fig. 1. A thermostat TH is provided in the high tension supply leads to the anodes in order to delay connection of the anode supply until the heaters are fully heated.

Across the high tension supplyleads there is provided, as indicated in: Figs. 1 and 2, a neon stablliser B of known construction which serves two purposes. Firstly, as the stabilizer S is shunted across the high tension source HT it prevents the voltage on the anodes of the relays V1 and Vi from rising above the normal working voltage which is important since there is a definite relathere is adefinite minimum control voltage which will prevent anode current flow. It is, therefore,

necessary to prevent surges in the anode-voltage in order to guard against any unwanted operation oi the gas-filled relays. Further, it is important The valve will, therefore, be comfor the emcient performance of the fast operated relays in the anode circuits of the gas-filled relays- I that their operating current should be maintained steady within reasonable limits. As is known, a

neon stabiliser is a gas discharge valve having a neon filling. The discharge strikes at a predetermined value of the voltage across the valve and substantially prevents any rise of the voltage beyond the predetermined value.

The second function of the neon stabiliser is in conjunction with therelay N (see Figs. 1 and a 2) which ensures that the recording always starts 03 at the Agrcup of fast relays. It will beseen that in the quiescent state the anode circuits of. both gas-filled relays Vrand V2 are broken at the various :1 contacts.

for pro- As soon as the anode place through the gas-filled relay V2.

supply is switched on by the thermostat, the voltage under no load conditions is sufllcient to cause the neon stabiliser S to strike and the current through it will operate relay N which closes its contact n (see Fig. 1) to prepare the A group of relays, thus ensuring that this group is the first to be operated. As soon as the recording commences thecurrent taken by the recording relays reduces the current through the neon stabiliser S to the point where the relay N releases and all subsequent operation of the A group of relays takes place in the normal sequence.

In the anode circuit of each gas filled relay is connected a series of high speed recording relays. Relay groups A, C, E, G, I (see Fig. 1) form one series and relay groups B, D, F, H, J form the other. Each relay group prepares'the circuit for the next in succession, that is group A prepares the circuit for group B, and group B for group C and so on, and it will be seen, therefore, that as each relay is operated for one 100th of a second the operationoi the complete series A to J will take one tenth second. lay group J operating prepares the circuit for relay group A and so the sequence is repeated successively throughout the recording.

Immediately the race starting device is operated. the start" relay contact in the primary circuit of the transformer T closes. As previously explained the grid control voltage on the two gas-filled relays is varied at 50 cycles causing anode current to flow in each alternately. The first gas-filled relay to discharge is V1 over isclosed the relay X (Fig. 3) operates andis locked up over its contact or andinterruptor springs dma. Relay OY is operated in parallel with relay OX and energises over its contact 01/ the driving magnet DMs. When the magnet DM: is energised the interruptor springs dma are opened, the tenth makes one step and the de-energised.

At each th step of the 10th seconds rotary switch, the driving magnet DM: of the units seconds rotary switch is energised from earth over contact P1 the closed start contact, the wiper. and bank of the tenths second switch. When the tenths second switch makes its'next step this circuit is broken, DM: is de-energised and causes the units seconds switch to make one step. At each tenth step of the units seconds switch the driving magnet DM1 of the tens seconds switch is energised from earth over con tact 121, the closed start contact, contact p2 relays OX and OY are and wiper and bank of the units seconds switch.

When this switch makes its next step the connection is broken, DM1 is de-energised and the ten seconds switch makes one step., If longer time periods are to be indicated, further rotary switches are provided for indicating the units the contact 12. The relays AX, AY, AZ are thus operated. Relay AX is fast to operate and closes its contact ax to provide a locking circuit guarding against the release of contact n. Relay AY prepares the circuit for the B group of relays by closing its contact aybut this group will not operate at this stage as no discharge is taking Relay AZ operates its contact az (not specifically shown but being one of the contacts designated contacts of Z relays, see left handside of Fig. 1 and right hand side of Fig. 3A) to provide a marking potential on the first contact on the bank of the 100th seconds rotary switch S1.

When the gas-filled relay V2 strikes as previously explained, gas-filled relay V1 is extinguished. Relays BX, BY' and BZ are therefore operated and relays AX, AY and AZ released.

All the Y relays, however, are slightly slow to release and as all X relays are fast to operate, BX will operate to close its contact ha; and lock up the B group of relays before contact ay opens. Relay BY prepares the circuit for the C series by closing its contact by but again this'C group will not operate since now no discharge is taking place through the gas-filled relay V1. Relay BZ provides a marking contact on the second contact of the bank of the rotary switch S1.

The foregoing sequence of operations is continued for each group of relays, each Y relay preparing the circuit for the next group, each X relay locking its own group, and each IZ relay marking the appropriate contact on the bank of the 100th seconds rotary switch.. At the end of the chain, relay JY prepares the circuit for the A group and so the sequence is repeated until the stop contact in the primary circuit minutes and the tens minutes and so on, and the method of stepping-up the switches of higher denominations may be effected as explained in the specification of my British Patent No. 466,- 861.

The switches used arenorm'al 25 point switches with staggered wipers, .thus giving over two consecutive banks, contact points for a complete revolution of the wipers. The homing contact for the wipers is also the 50th contact, and whilst an impulse must be sent to the next switch each time the wipers pass over this contact, an impulse must not be sent when the wipers are in their home position. To achieve this, contacts ya: and gba actuated by.relays GA and GB respectively are provided. These contacts keep the impulse circuitsopen in the home position or the wipers. When the wipers of the tenths second and units seconds switches move of! their home position onto the first contacts of their banks, the relays GB and GA respectively are energised and lock up over the contacts gin and gar respectively, closing also the contacts ab: and gun, thus enabling the impulses to be sent. when now the wipers pass oyer the 50th contact.

ing potential on the bank of the wiper S1, (see Figs. 1, 3 and 3A, Fig. 1 being somewhat diagramrnatical), which is a wiper of the hundredth second switch. The stop switch closes also the contacts 892 and spa. The contact 82): completes the circuit for a relay D, which closes contact (11 and thus energises the driving magnet DM4. Relay D also closes contact (12 which completes the circuit for relay C. When relay C operates contact or is opened and relay D is released, thereby contact d1 is opened and the driving magnet DM4 of the hundredth second switch is de-energised, whereupon this switch makes one step. Contact d: is also opened and thus relay C is de-energised, cr is closed and relay D'is again energised. Relays D and C thus continue to operate alternately stepping the hundredth second switch each time its driving magnet DM4 is deenergised. When the wiper S1 reaches the contact marked by a Z relay, relay K operates and seconds rotary switch 4 a contact is disconnects the circuit for relay D and make only a step when the the switch reaches its home position.

' stepping circuit second switch is driven her as the preceding n the tenths second switch has reached its home 7 :position earth is extended tact in (see Fig.1?) int ti'i i flfibncurrent prevents further movement of the hundredth second switch.

.11 it happens that at the end of the recording either or both of the tenths and thehundredths second switches stand on the tenth, twentieth, or fiftieth step, the stepping circuit o'fthe next switch is completed and its driving magnet energised. Since the switches driving magnet is deenergised contact spa is provided to effect the de-energising of the driving magnet. When the stop switch is actuated the contact spa is closed and relay P is operated opening the contacts In and pr which disconnect the driving magnets DMi'and DMi of the ten seconds and units seconds switches thus allowing either or both of these switches to complete the final step if their driving magnets were Just energised at the moment the stop switch was actuated.

The operation of the start" and "stop contacts may be manual or automatic by means of photo-electric or other suitable known devices.

Thestarting and stopping impulses may be pure: 1y transient eifects persisting for a few microseconds only, or the duration of the operation causing the device to start may persist after the receipt of the impulse causing it to stop. I On the other hand the time interval recorded can be that for any single operation provided only that the instant of starting and stopping the operation can be converted into electrical impulses. In order to prepare the apparatus for use again, a re-set switch is operated which restores all the rotary switches toa normal position" and 5 resets the discharge relays V1 and V2. The reset switch actuates the'contacts R1 to Rs shown in Figs. 3 and 3A and contact R1 shown in Fig. 2. All the contacts R1 to R1 operate simultaneously in the manner now to be described. While in the drawings all the switches and contacts areshown in their initial position, it will be appreciated that when the reset switch is actuated a particular time interval has been recorded and the switches and contacts are in their working position as described above.

- "By closing the, contact R1 earth is extended irom the ten seconds'wiper through the interruptor springs rim; to the driving magnet DMI which is energised. When DM is energised the rm interruptor springs dtni open and DM; is deenergised. The ten seconds switch makes one step and the interruptor-springs dmi are closed again. 'I'his cycle of operation continues until It." In the home position of the ten seconds switch. earth is extended to the wipers of the units seconds switch. and since contact R2 is closed the units seconds switch is driven home in the same manner as-Just described with regard to the m ten seconds switch.- 'When the units seconds switch reaches its home position earth is extended to the tenths second switch. As. will be seen from Fig. 3,; the contacts R: change the second switch to M of the tenth v a circuit similar to those employed for the ten seconds and units seconds switch. The tenths home in the-same mantime switches, and when 4 to the hundredth! sidfildiwiteh which mean 8WD time while contact 'Rsis closed. The contactssRs and R0 unlock the relays GA and GR respectively. m c

I the plane of the I Moreover, whilst I have each wiper associated with a row of 10 contacts,

" -ing m the position 0! these ply to the discharge relays Sh and V2. Thereby the X, Y and Z relays which were locked by their corresponding :0 contact (see Fig. 1) are released. The start, stop and reset switches are finally brought into their original position, either manually or automatically, and the arrangement is again ready for use.

The time interval recorded by the arrangement illustrated in- Fig. 3 is indicated by a numerical time indicator, comprising iour indicating units,

each unit being controlled by .one oi-the fo'urtime switches.

Fig. 4.- shows the two units 4 and 5 controlled by the units seconds switch and the ten seconds switch respectively and their connectionsto these switches, the units-for the tenths and the hundreths second switches and their connections to these switches being similar to the unit t and its connections. The units 6 and s have each 8 lamps A 15 H and A", B H respectively. One terminal of each lamp is permanently connected through a terminal :01, 0:2 respectively to one pole of a battery the other pole of which is earthed. The other terminals of the lamps are connected to terminals in, bi hi, and as, b: h: respectively. Each unit is adapted to display the numerals l, 2 9 and 0,

when'the appropriate lamps are lighted. For example, numeral 1 is displayed when the lamps A and B are lighted, numeral 2 when the lamps C, G, E, B and F are lighted, numeral 7, when the lamps C, D and B are lighted. It will be metals can be obtained.

Each of the time switches has eight additional wipers and corresponding rows of contact (not shown in Fig. 3). In Fig. 4, the eight addi- .tional wipers oi the units seconds switches, are indicated by U, I seconds switch by 2 2 2'. The corresponding rows of contacts are shown developed on drawing and the wipers. will step vertically from one contact to the next, but it will be understood that in the actual construction the contacts shown will be arranged in semi-circular banks, and the wipers will rotate about a shaft at the centre of the banks. shown. for simplicity,

in actual construction each wiper will comprise two arms each of which is associated with a bank 25 contacts, the arrangement being such that for a complete revolution 01 the wiper fifty contact points are obtained for each wiper.

The arrangement 3) that is to say after the stop switch has been actuated and the-hundredth second switch has found, its marked position. When contacts k1 is closed earth is extended to the wipers I I I. which causes the numeral correspondair d a I r .It should be understood that the mains sup-.

in Fig.2) for the discharge including the neon stabiliser the circuit arrangements ply circuit (shown relays V1 and Va, and the thermostat,

shown in Fig. 3 ior seconds switches-the circuits shown in Fig. 3

readily appreciated how any of the other nui l and those oi the ten- I I shown in Fig. 4 operates as follows: when the start switch is operated the wipers 2 2 wipers to be dis-' the ten-seconds and units for resett ng the arrangement. and that part of the arrangement which is illustrated in Fig. 4, in themselves form no part of my invention.

It should be clearly understood that the drawings are given for explanatory purpose and by way of example only and that modifications of the specific embodiment described and illustrated are possible without departing from the scope of my-invention which is defined by the appended claims.

I claim:

1. An electric timing device comprising means for generating timed impulses, a series of impulse responsive devices, means for successively actuating said devices by said impulses, a stop switch, means for marking that impulse responsive device which was last actuated when the stop switch is operated, an indicator, and means for operating the indicator in accordance with the marked impulse responsive device.

2. A stop watchcomprising an operating mechanism, means for starting said mechanism, means for stopping said mechanism, a visual indicator comprising a plurality of indicating un ts for different denominations, means for actuating at least one 01' said units continuously during the operation or said mechanism, and means for actuating at least one of said units only after-the stopping means have been actuated.

3. An electric timing device comprising means for generating a tralnbi' timed electric impulses, a series of impulse responsive devices, means for actuating each impulse responsive device in turn by successive impulses in said train, a starting switch, control means for ensuring that a certain impulse responsive device of said series is the first to be operated after actuation of said starting switch, a stopping switch, means for marking that impulse responsive device which was last actuated when the stopping switch is operated, an indicating device and means for operating said indicating device in accordance with the marked impulse responsive device.

4. An electric stop watch utilising positive and negative halves of a 50 cycle alternating current for furnishing hundredth of a second impulses, in which there is provided a first series oiimpulse responsive devices, each of which is responsive to an impulse corresponding to a positive half-cycle, a second series 01' impulse rearranged to be actuated one by the positive and the other by the negative half-cycles of the alter nating current source, together with means for .deionising one relay substantially immediately upon the ionisation of the other.

7. An electric stop watch according to claim 5, wherein the positive and negative half-cycles of the alternating current are distributed to the first and second series of impulse responsive devices by means of a control circuit comprising a pair of gas-filled relays alternately energised at each half-wave of the alternating current, an anode in each relay, a discharge path interconnecting the two anodes, the arrangement of the path and relays being such that the path is charged when one of the relays is energised and discharged through the other relay when that relay energises, thereby causing a potential to sponsive devices each or which is responsive to an impulse corresponding to negative hair-cycle, and means for operating the impulse responsive devices in each series successively.

5. An electric stop watch utilising positive and negative halves of a cycle alternating current for furnishing hundredth of a second impulses. in which there is provided a first series of line pulse responsive devices, each or which is responsive to animpulse corresponding to a positive halt-cycle a second series of impulse responsive devices each of which is responsive to an impulse corresponding to a negative halfcycle, means for operating the impulse responsive devices in each series successively and means for operating an indicating device in accordance with the last impulse responsive device operated when .the stopping switch is operated. 1

6. An electric stop watch according to claim 5, wherein the positive and negative halt-cycles of be established on the anode of the one relay momentarily opposing its anode potential whereby that relay is de-ionised substantially immediately.

8. An electric stop watch according to claim 5, wherein the positive and negative half-cycles of the alternating current are distributed to the first and second series of impulse responsive devices by means of a control circuit comprising a pair of gas discharge relays connected in opposition, an anode in each of said relays, and a discharge path, including a condenser, interconnecting the anodes of said relays.

9. An electric stop watch according to claim 5, wherein the positive and negative half-cycles of the alternating current are distributed to the first and second series of impulse responsive devices by means of a control circuit comprising in combination a transformer having; primary and secondary windings, a first gas discharge relay, an anode, a control grid and a cathode within said relay, a circuit connection between said grid and one end of said secondary winding, a circuit connection between said cathode and a neutral point on said secondary winding, a second gas discharge relay, an anode, a control grid and a cathode within said second relay, a circuit connection between said grid of said second relay and the other end-of said secondary winding, 9. first circuit connection between said anodes and including the anode-cathode 'path 01 the relays and the series 01 impulse responsive devices responsivetocurrents flowing in said anode-cathode paths, and a second circuit connection between said anodes including a condenser.

EDWARD BHIPTON. 

